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81.
Due to the significant growth of the market for numerous flexible electronic devices, demand for mechanically stable indium zinc tin oxide (IZTO) based flexible transparent electrodes has recently expanded substantially. So, we have attempted to increase the mechanical stability of an IZTO based flexible transparent electrode by forming an ultrathin interlayer of an organic semiconductor polystyrene sulfonate doped polyaniline (PANI:PSS). According to the results of the systematic investigation, the PANI:PSS treated IZTO film can preserve 97.50% of its initial average transmittance (AVT) value (83.07%) after 20,000 bending cycles, but the bare IZTO film can retain only 89.00% of its initial AVT value (86.40%) after the same treatment. Furthermore, the PANI:PSS treatment has benefited in the reduction of IZTO film sheet resistance from 17.38 to 16.91 Ω/sq. Scanning electron microscopy images have indicated that the presence of a PANI:PSS interlayer on the IZTO film prevents the formation of fractures on the inorganic IZTO layer when mechanical stress is applied. 相似文献
82.
83.
We have measured magnetic penetration depth(0) of high-T
c YBCO samples of different density by the cavity resonant frequency shift method at 10, 16.65, and 22.3 GHz microwave frequencies. The value of(0) at 10 GHz is found to decrease from 5850 Å to 2550 Å as the density of the sample increases from 4.4 to 5.3 g/cm3. The results of the frequency response of the penetration depth show a fairly constant value of(0) for all the three samples in the frequency range 10–22.3 GHz. The wide variation observed in the value of(0) for different density samples has been explained in terms of varying Josephson coupling strength in these ceramics. 相似文献
84.
Reuben S Chua CL Fam KD Thian ZY Kang MK Swarup S 《Water science and technology》2012,65(10):1869-1874
Microbial loads in freshwater systems have important implications in biogeochemical cycling in urban environments. Immersed surfaces in freshwaters provide surfaces for bacterial attachment and growth. Microorganisms that adhere initially to these surfaces play a critical role in biofilm formation and sustenance. Currently, there is little understanding on the type of organisms that initially adhere to different surfaces in urban canals. In this study, water from an urban stormwater canal was employed to allow bacteria to attach to different surfaces in a flowcell apparatus and understand the differences and changes in bacterial community structure. Bacterial communities were highly diverse on different surfaces as indicated by Jaccard's indices of 0.14-0.56. Bacteria on aluminium were the most diverse and on Plexiglas the least. Bacterial communities were highly dynamic in the early attachment phase and it changed by 59% between 3 and 6 h on aluminium. Specificity of attachment to surfaces was observed for some bacteria. Judicious use of materials in urban aquatic environment would help mitigate microbial load in urban waters. 相似文献
85.
Security is recognized as an important problem in planning, design and operation stages of electric power systems. Power system security assessment deals with the system’s ability to continue to provide service in the event of an unforeseen contingency. This paper proposes a particle swarm optimization (PSO) based classification for static security evaluation in power systems. A straightforward and quick procedure is used to select a small number of variables as features from a large set of variables which are normally available in power systems. A simple first order security function is designed using the selected features for classification. The training of weights in the classifier function (security function) is carried out by PSO technique. The PSO algorithm has minimized the error rate in classification. The procedure to determine the security function (classifier) is discussed. The performance of the algorithm is tested on IEEE 14 Bus, IEEE 57 Bus and IEEE 118 Bus systems. Simulation results show that the PSO classifier gives a fairly high classification accuracy and less misclassification rate. 相似文献
86.
Radial and angular moment invariants for image identification 总被引:1,自引:0,他引:1
Radial and angular moments of images are presented and methods are shown for deriving moment functions that are invariant with respect to rotation, translation, reflection, and size changes without the aid of the theory of algebraic invariants. Hu's invariants are expressed in terms of these radial and angular moments and it is claimed that this facilitates visual inspection of invariance properties. 相似文献
87.
Three Xband avalanche-diode iris mounts of identical design were cascaded to form a composite oscillator structure. It has been experimentally established that highly efficient power addition can be obtained with this scheme. Matching the individual diode characteristics and spacing between the diodes are not too critical. 相似文献
88.
S Rami Reddy G Narasimhulu PM Reddy V Sridhar GHS Reddi 《Nutrient Cycling in Agroecosystems》1983,4(4):381-385
Experiments were conducted on sandy loam soils of Tirupati campus of Andhra Pradesh Agricultural University for two rainy seaons of 1980 and 1981 to study the effect of split application of NPK fertilizers on Spanish bunch groundnut. The fertilizer doses were 40 N, 20 P and 40 K kg ha–1 in 1980 and 30 N, 10 P and 25 K kg ha–1 in 1981.In 1980, uptake of N (48 kg ha–1), P (7 kg ha–1) and K (37 kg ha–1) was maximum with the application of 10 N, 5 P and entire 40 K kg ha–1 as basal and 30 N and 15 P kg ha–1 at 30 days after sowing, leading to highest pod yield (0.76 t ha–1). In 1981, application of 20 N, 10 P and 25 K kg ha–1 as basal dose and 20 N kg ha–1 at 30 days after seeding resulted in highest uptake of N (114 kg ha–1), P (17 kg ha–1) and K (58 kg ha–1) and hence the pod yield (2.36 t ha–1).Differences in the uptake of NPK and pod yield in 1980 and 1981 was due to variation in total rainfall and its distribution during the crop period. Rainfall was equally distributed throughout the crop period in 1981, whereas there were two prolonged dry spells of more than 40 days in 1980. 相似文献
89.
A long term field experiment was conducted for 8 years during 1994–2001 to evaluate the effect of N, P, K and Zn fertilizer
use alone and in combination with gypsum, farmyard manure (FYM) and pressmud on changes in soil properties and yields of rice
and wheat under continuous use of sodic irrigation water (residual sodium carbonate (RSC) 8.5 meq l−1, and sodium adsorption ratio (SAR) 8.8 (m mol/l)1/2 at Bhaini Majra experimental farm of Central Soil Salinity Research Institute, Karnal, India. Continuous use of fertilizer
N alone (120 kg ha−1) or in combination with P and K significantly improved rice and wheat yields over control (no fertilizer). Phosphorus applied
at the rate of 26 kg P ha−1 each to rice and wheat significantly improved the yields and led to a considerable build up in available soil P. When N alone
was applied, available soil P and K declined from the initial level of 14.8 and 275 kg ha−1 to 8.5 and 250 kg ha−1 respectively. Potassium applied at a rate of 42 kg K ha−1 to both crops had no effect on yields. Response of rice to Zinc application occurred since 1997 when DTPA extractable Zn
declined to 1.48 kg ha−1 from the initial level of 1.99 kg ha−1. Farmyard manure 10 Mg ha−1, gypsum 5 Mg ha−1 and pressmud 10 Mg ha−1 along with NPK fertilizer use significantly enhanced yields over NPK treatment alone. Continuous cropping with sodic water
and inorganic fertilizer use for 8 years slightly decreased the soil pHe and SAR from the initial value of 8.6 and 29.0 to 8.50 and 18.7 respectively. However, treatments involving the use of gypsum,
FYM and pressmud significantly decreased the soil pH and SAR over inorganic fertilizer treatments and control. Nitrogen, phosphorus
and zinc uptake were far less than additions made by fertilizer. The actual soil N balance was much lower than the expected
balance thereby indicating large losses of N from the soil. There was a negative potassium balance due to greater removal
by the crops when compared to K additions. The results suggest that either gypsum or FYM/pressmud along with recommended dose
of fertilizers must be used to sustain the productivity of rice – wheat system in areas having sodic ground water for irrigation. 相似文献
90.
Shye Alex Blomstedt Joseph Moseley Tipp Reddi Vijay Janapa Connors Daniel A. 《Dependable and Secure Computing, IEEE Transactions on》2009,6(2):135-148
Transient faults are emerging as a critical concern in the reliability of general-purpose microprocessors. As architectural trends point toward multicore designs, there is substantial interest in adapting such parallel hardware resources for transient fault tolerance. This paper presents process-level redundancy (PLR), a software technique for transient fault tolerance, which leverages multiple cores for low overhead. PLR creates a set of redundant processes per application process and systematically compares the processes to guarantee correct execution. Redundancy at the process level allows the operating system to freely schedule the processes across all available hardware resources. PLR uses a software-centric approach to transient fault tolerance, which shifts the focus from ensuring correct hardware execution to ensuring correct software execution. As a result, many benign faults that do not propagate to affect program correctness can be safely ignored. A real prototype is presented that is designed to be transparent to the application and can run on general-purpose single-threaded programs without modifications to the program, operating system, or underlying hardware. The system is evaluated for fault coverage and performance on a four-way SMP machine and provides improved performance over existing software transient fault tolerance techniques with a 16.9 percent overhead for fault detection on a set of optimized SPEC2000 binaries. 相似文献